I currently have an ez-3 usx and really like it. I am also thinking of building a ez-sport type clone, just for fun and to see if I can do it. I recently saw a few online recumbent suppliers offering a ez-1 seat kit which is identicle to my usx. it included the track,seat,seat back,rear supports,etc.
I went to my local bike shop where I bought my usx and asked him to find out the priceof said kit. he couldnt find any info on this"kit" so I am wondering if it is actually offered as a kit from sun or as a kit from the online suppliers. does anyone know a j&b or sun part number for this "kit"?
If i can get the complete seat assembly in kit form it would make completing the clone frame really easy as far as the seating area is concerned. thanks

The EZ 1 seat you usually see advertised is approx 12 pounds! It has the steel frame and base and I think you can get it at poweroncycling.com. You could also go to recycledrecumbent.com and get a mesh seat from Andrew Carson. Very comfy and about a third of the weight at a reasonable price. Andrew makes and instructs on how to make, EZ clones. He will be a good source and is readily available to help you if needed.

Here is a paragraph from the Recumbent Cyclist News EZ1 review last year:

UPGRADES: It’s possible to lighten up the EZ1 by ordering an aluminum seat back ($90 retail, J&B part #67455 — see J&B note at end of article), aluminum seat lower struts ($12 retail; J&B part #67457), upper struts ($12 retail; J&B part #67456) and alloy handlebars ($70 retail; J&B part #67349). This might save two or three pounds. Lighter wheels and tires are also possible. An EZ Sport 20” fork (J&B part #27664 black or #27665 silver) will also fit, so you can convert to a 20”/20”. If you are going to make all of these upgrades, you should probably just buy the lighter AX model.

It seems to me that the seat base on the EZ1 steel vs. alum was not interchangeable due to square tubing size. You might want to check that before you order.